In the morning, Frenchman's about to baptise once more (6)
I believe the answer is:
rename
'baptise once more' is the definition.
I can't tell whether this defines the answer.
'in the morning frenchman's about' is the wordplay.
'in the morning' becomes 'am' (AM on a clock).
'frenchman' becomes 'rene' (common French name).
'about' is an insertion indicator.
'am' put into 'rene' is 'RENAME'.
'to' acts as a link.
Can you help me to learn more?
(Other definitions for rename that I've seen before include "Give a new title to" , "Alter title of" , "Call again" , "Meaner (anag.)" , "Confer new appellation of meaner sort" .)